[all slogans are subject to change]

Wehrmacht

"It's never too late to find your way."

Schutzstaffel

"Brothers first. Fuck everyone else."

Third Reich

"My nation, my soul."

Prussia

"If life is a game, might as well have fun with it."

Fascist Italy

"Fight for your real friends."

Japanese Empire

"I conquer island nations. And everyone is an island nation."

BONUS:

Iremacht

"People are bitches, like my great-grandfather.... Oh well, the less, the better right?"